1 files changed, 44 insertions, 18 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 7e7c3969f7a..b0e4ddca6c1 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -66,7 +66,8 @@ static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {}
 #endif
 
 #if defined(MMU_DEBUG) || defined(AUDIT)
-static int dbg = 1;
+static int dbg = 0;
+module_param(dbg, bool, 0644);
 #endif
 
 #ifndef MMU_DEBUG
@@ -776,6 +777,15 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
         BUG();
 }
 
+static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
+                                    struct kvm_mmu_page *sp)
+{
+        int i;
+
+        for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
+                sp->spt[i] = shadow_trap_nonpresent_pte;
+}
+
 static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn)
 {
         unsigned index;
@@ -841,7 +851,10 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
         hlist_add_head(&sp->hash_link, bucket);
         if (!metaphysical)
                 rmap_write_protect(vcpu->kvm, gfn);
-        vcpu->arch.mmu.prefetch_page(vcpu, sp);
+        if (shadow_trap_nonpresent_pte != shadow_notrap_nonpresent_pte)
+                vcpu->arch.mmu.prefetch_page(vcpu, sp);
+        else
+                nonpaging_prefetch_page(vcpu, sp);
         return sp;
 }
 
@@ -917,14 +930,17 @@ static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
         }
         kvm_mmu_page_unlink_children(kvm, sp);
         if (!sp->root_count) {
-                if (!sp->role.metaphysical)
+                if (!sp->role.metaphysical && !sp->role.invalid)
                         unaccount_shadowed(kvm, sp->gfn);
                 hlist_del(&sp->hash_link);
                 kvm_mmu_free_page(kvm, sp);
         } else {
+                int invalid = sp->role.invalid;
                 list_move(&sp->link, &kvm->arch.active_mmu_pages);
                 sp->role.invalid = 1;
                 kvm_reload_remote_mmus(kvm);
+                if (!sp->role.metaphysical && !invalid)
+                        unaccount_shadowed(kvm, sp->gfn);
         }
         kvm_mmu_reset_last_pte_updated(kvm);
 }
@@ -1103,7 +1119,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
                 mark_page_dirty(vcpu->kvm, gfn);
 
         pgprintk("%s: setting spte %llx\n", __func__, spte);
-        pgprintk("instantiating %s PTE (%s) at %d (%llx) addr %llx\n",
+        pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
                  (spte&PT_PAGE_SIZE_MASK)? "2MB" : "4kB",
                  (spte&PT_WRITABLE_MASK)?"RW":"R", gfn, spte, shadow_pte);
         set_shadow_pte(shadow_pte, spte);
@@ -1122,8 +1138,10 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
                 else
                         kvm_release_pfn_clean(pfn);
         }
-        if (!ptwrite || !*ptwrite)
+        if (speculative) {
                 vcpu->arch.last_pte_updated = shadow_pte;
+                vcpu->arch.last_pte_gfn = gfn;
+        }
 }
 
 static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
@@ -1171,9 +1189,10 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
                                 return -ENOMEM;
                         }
 
-                        table[index] = __pa(new_table->spt)
-                                | PT_PRESENT_MASK | PT_WRITABLE_MASK
-                                | shadow_user_mask | shadow_x_mask;
+                        set_shadow_pte(&table[index],
+                                       __pa(new_table->spt)
+                                       | PT_PRESENT_MASK | PT_WRITABLE_MASK
+                                       | shadow_user_mask | shadow_x_mask);
                 }
                 table_addr = table[index] & PT64_BASE_ADDR_MASK;
         }
@@ -1211,15 +1230,6 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
 }
 
 
-static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
-                                    struct kvm_mmu_page *sp)
-{
-        int i;
-
-        for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
-                sp->spt[i] = shadow_trap_nonpresent_pte;
-}
-
 static void mmu_free_roots(struct kvm_vcpu *vcpu)
 {
         int i;
@@ -1671,6 +1681,18 @@ static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
         vcpu->arch.update_pte.pfn = pfn;
 }
 
+static void kvm_mmu_access_page(struct kvm_vcpu *vcpu, gfn_t gfn)
+{
+        u64 *spte = vcpu->arch.last_pte_updated;
+
+        if (spte
+            && vcpu->arch.last_pte_gfn == gfn
+            && shadow_accessed_mask
+            && !(*spte & shadow_accessed_mask)
+            && is_shadow_present_pte(*spte))
+                set_bit(PT_ACCESSED_SHIFT, (unsigned long *)spte);
+}
+
 void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
                        const u8 *new, int bytes)
 {
@@ -1694,6 +1716,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
         pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes);
         mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes);
         spin_lock(&vcpu->kvm->mmu_lock);
+        kvm_mmu_access_page(vcpu, gfn);
         kvm_mmu_free_some_pages(vcpu);
         ++vcpu->kvm->stat.mmu_pte_write;
         kvm_mmu_audit(vcpu, "pre pte write");
@@ -1948,7 +1971,7 @@ void kvm_mmu_zap_all(struct kvm *kvm)
         kvm_flush_remote_tlbs(kvm);
 }
 
-void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm)
+static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm)
 {
         struct kvm_mmu_page *page;
 
@@ -1968,6 +1991,8 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask)
         list_for_each_entry(kvm, &vm_list, vm_list) {
                 int npages;
 
+                if (!down_read_trylock(&kvm->slots_lock))
+                        continue;
                 spin_lock(&kvm->mmu_lock);
                 npages = kvm->arch.n_alloc_mmu_pages -
                          kvm->arch.n_free_mmu_pages;
@@ -1980,6 +2005,7 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask)
                 nr_to_scan--;
 
                 spin_unlock(&kvm->mmu_lock);
+                up_read(&kvm->slots_lock);
         }
         if (kvm_freed)
                 list_move_tail(&kvm_freed->vm_list, &vm_list);